The present invention relates to an apparatus for extracting water from the atmosphere by using a heat pump.
Water extracting devices are known in many different modifications, for example, as so called dehumidifiers. Moreover, devices are known which are used in extracting fresh water from the ocean, whereby the heretofore used methods employ the principle of expansion evaporation.
German patent publications Nos. 1,717,080 and 1,717,081 describe expansion evaporation methods for extracting fresh water from watery solutions, whereby a so called multiple expansion evaporation is used. Such evaporators comprise a row of expansion stages operating with successively lower temperatures. Bridges are arranged between the stages. The hot solution is cooled down on the evaporator side from step-to-step and successively through expansion evaporation, whereupon it is supplied to the condensation side where a heat exchange will occur.
Another method is described in German patent publication No. 2,236,519. In this apparatus the raw water which has been preheated in the condensors of the expansion evaporator is supplied to a flow-through vaporizer where it is partly vaporized and then the vapor or steam is brought to a higher temperature level by means of a heat pump to serve as a heating medium for the flow-through vaporizer, wherein the heat is given off and the distillate is supplied to the expansion evaporator.
All of the above discussed prior art methods operate according to the principle of expansion vaporization. Nevertheless these methods require an aqueous solution for recovering water. As a result, it is necessary that such prior art devices are constructed as stationary plans and it is not possible to make them portable, especially due to the weight of the entire plant structure, which is relatively expensive and technically involved.
German patent publication No. 2,112,362 discloses an arrangement of several heat pump circuits arranged in series with each other. In this known apparatus the environmental heat is brought to a higher temperature in stages, whereby each following heat pump stage uses for its starting base the hot side of the next lower heat pump stage. Although this arrangement employs air, among other media, for the coupling of the individual heat pumps, no water is extracted from such air when it is used.